Guo Chenchen, Khengar Rajeshree H, Sun Mingjing, Wang Zheng, Fan Aiping, Zhao Yanjun
Tianjin Key Laboratory for Modern Drug Delivery & High Efficiency School of Pharmaceutical Science & Technology, Tianjin University, 92 Weijin Road, Nankai District, Tianjin, 300072, China.
Pharm Res. 2014 Nov;31(11):3051-9. doi: 10.1007/s11095-014-1398-z. Epub 2014 May 8.
The acne skin is characteristic of a relatively lower pH microenvironment compared to the healthy skin. The aim of this work was to utilize such pH discrepancy as a site-specific trigger for on-demand topical adapalene delivery.
The anti-acne agent, adapalene, was encapsulated in acid-responsive polymer (Eudragit® EPO) nanocarriers via nanoprecipitation. The nanocarriers were characterized in terms of particle size, surface morphology, drug-carrier interaction, drug release and permeation.
Adapalene experienced a rapid release at pH 4.0 in contrast to that at pH 5.0 and 6.0. The permeation study using silicone membrane revealed a significant higher drug flux from the nanocarrier (6.5 ± 0.6 μg.cm(-2).h(-1)) in comparison to that (3.9 ± 0.4 μg.cm(-2).h(-1)) in the control vehicle (Transcutol®). The in vitro pig skin tape stripping study showed that at 24 h post dose-application the nanocarrier delivered the same amount of drug to the stratum corneum as the positive control vehicle did.
The acid-responsive nanocarriers hold promise for efficient adapalene delivery and thus improved acne therapy.
与健康皮肤相比，痤疮皮肤的特征在于pH值相对较低的微环境。本研究的目的是利用这种pH差异作为按需局部递送阿达帕林的位点特异性触发因素。
通过纳米沉淀法将抗痤疮药物阿达帕林包裹在酸响应性聚合物（Eudragit® EPO）纳米载体中。对纳米载体进行了粒径、表面形态、药物-载体相互作用、药物释放和渗透等方面的表征。
与pH 5.0和6.0时相比，阿达帕林在pH 4.0时快速释放。使用硅膜的渗透研究表明，纳米载体的药物通量（6.5±0.6 μg·cm-2·h-1）显著高于对照载体（Transcutol®）（3.9±0.4 μg·cm-2·h-1）。体外猪皮胶带剥离研究表明，给药后24小时，纳米载体向角质层递送的药物量与阳性对照载体相同。
酸响应性纳米载体有望实现高效的阿达帕林递送，从而改善痤疮治疗。
